Synonyms for persistent

Adjective

1. persistent, relentless, unrelenting, continual (vs. sporadic)

usage: never-ceasing; "the relentless beat of the drums"

2. haunting, persistent, unforgettable (vs. forgettable)

usage: continually recurring to the mind; "haunting memories"; "the cathedral organ and the distant voices have a haunting beauty"- Claudia Cassidy

3. persistent (vs. caducous), lasting

usage: retained; not shed; "persistent leaves remain attached past maturity"; "the persistent gills of fishes"